Hi again,
On 09.02.2015 14:33, Kaspar Schleiser wrote:
Hi Joakim,
On 02/09/15 14:20, Joakim Gebart wrote:
Has anyone measured the cost of the thread context switching on the
different platforms? I'm mainly interested in Cortex-M4 (Kinetis). This
would be a good indication of how "slow" an I/O
Hi,
we do indeed have a number of places in the driver code, where busy
waiting is used. The reason for this is mostly missing man power to
implement better versions of the same driver. The most important fact
here is, that you can re-implement a driver in a more efficient way
completely tran
Hi Joakim,
On 02/09/15 14:20, Joakim Gebart wrote:
Has anyone measured the cost of the thread context switching on the
different platforms? I'm mainly interested in Cortex-M4 (Kinetis). This
would be a good indication of how "slow" an I/O device has to be before
it is worth it to manually yield
I was actually writing on a post for this list along the same theme when I
saw your message. The main reason I see for removing the busy waits is that
you can lower the power consumption if you can let the CPU core sleep while
the peripheral is working, either using interrupts or DMA for the transf
On Sun, Feb 08, 2015 at 04:48:00PM +0100, Ludwig Ortmann wrote:
> Hi Frank,
>
> On Sun, Feb 08, 2015 at 11:47:25AM +0100, Frank Holtz wrote:
> > i have looked into periph drivers and found a lot of single line "while"
> > statements waiting for finishing things.
> > ...
> > Slow devices like ADC,
Hi Frank,
On Sun, Feb 08, 2015 at 11:47:25AM +0100, Frank Holtz wrote:
> i have looked into periph drivers and found a lot of single line "while"
> statements waiting for finishing things.
> ...
> Slow devices like ADC, Flash, UART or Random number generation are
> wasting a lot of CPU cycles whi
Hello,
i have looked into periph drivers and found a lot of single line "while"
statements waiting for finishing things.
stm32f4 -> 26 statements
nrf51822 -> 4 statements
atmega2560 -> 8 statements
cc2538 -> 4 statements
sam3x8e -> 13 statements
...
Slow devices like ADC, Flash, UART or Random n
